326 BAY, SEA OR DIVING DUCKS 



a complete postnuptial moult in August and September, during which the flight- 

 feathers are shed and the birds are incapable of flight until these are renewed. 



AUTUMN PLUMAGE: Same as winter plumage. 



ADULT FEMALE. Head and neck, brownish black, sometimes with two in- 

 distinct whitish spots in region of ear and before eye; bill, dull black, more or less 

 mixed with whitish on upper mandible, sometimes a patch of deep pink on sides, 

 knob less prominent than in male; eye, dark brown. Body. Entire body blackish 

 brown; some feathers of scapulars, sides and breast, edged with whitish; feet, light 

 brownish red; webs blackish. Tail and its coverts, blackish brown. Wings, blackish 

 brown, with white speculum; lining and axillars, same as in male. 



JUVENILE. During first autumn the sexes are alike, dark sooty brown, blackish 

 on crown and back, paler on breast, sometimes even whitish; conspicuous white 

 patches on sides of head in ear region, and in front of eye; eye of male, light 

 grey brown, of female, dark brown; feet of young male, as in adult female but 

 outer side of tarsus blackish; feet of young female with outer side of tarsus blackish, 

 but inner side of tarsus and toes, dull purplish brown. 



During winter, sexes begin to differentiate, males becoming blacker, females 

 browner; white face-patches become obliterated; bill of young male shows colour 

 but is not swollen at base. Second autumn, after first post-nuptial moult, when 

 14 or 15 months old, young males are practically adult, and eye becomes white; 

 bill not at full stage of development. Third autumn, after second postnuptial 

 moult, plumages are fully adult in both sexes. Wing of Both Sexes. As in adult 

 female but tertials, lesser and middle coverts, usually somewhat paler. Occasion- 

 ally, young female shows very much reduced white speculum, sometimes less than 

 an inch wide at tips. 



SPECIMEN IDENTIFICATION 



MALE. General effect: A very large, black duck, with white wing-patch. Chief 

 distinguishing features (a) hind toe with lobe, (b) white speculum, and small 

 white patch near eye, (c) feathering on ridge of bill extends nearly to nostril, 

 and feathering on sides of bill nearly as far as that on ridge, (d) head elongated, 

 slope of forehead follows line of bill. 



The White-winged Scoter is the only black duck of this continent with a 

 white speculum. (The European Velvet 

 Scoter, Melanitta fusca, is identical with 

 this species except for feature (c), the 



feathering on bill not extending so far 



towards the nostril.) 



FEMALE. General effect: A large, 



brownish-black duck, with a white wing-patch. Chief features (a) hind toe with 

 lobe, (b) white speculum, (c) and (d) same as in male. 



The white speculum will identify the female. It bears a closer resemblance 

 to its own mate than to any other duck, but is lighter coloured, and lacks the 

 red on upper mandible and the prominent knob at base of bill above. 



JUVENILE. The juveniles can always be distinguished from the juveniles and 

 adults of other scoters b^ the white speculum, and by features (c) and (d) above. 

 See "Description." 



